What is a waterproof power adapter? Detailed explanation of waterproof power supply!
What is a waterproof power adapter?
Waterproof power supply refers to multiple protections such as short circuit, overcurrent and overload when it is used under the condition of dustproof and waterproof grade ip6. So what is the dustproof and waterproof grade? Dustproof and waterproof grade IP67 (
Safe and dustproof, immersed in water for 15 cm to 1 m, can work normally); High power factor;
It has multiple protections such as short circuit, overcurrent and overload. 1. According to the driving mode, it can be divided into two categories (1)
The current output by constant current type a and constant current drive circuits is constant, while the output DC voltage changes within a certain range with the different load resistance values, and the load resistance value is small, the output voltage is low, and the greater the load resistance, the higher the output voltage;
B, constant current circuit is not afraid of load short circuit, but it is strictly prohibited to load completely open circuit.
C, constant current drive circuit is ideal to drive LED, but the price is relatively high.
D, should pay attention to the use of the maximum withstand current and voltage value, it limits the number of LED use; (2)
Voltage stabilizing type a. When various parameters in the voltage stabilizing circuit are determined, the output voltage is fixed, while the output current changes with the increase or decrease of the load;
B, voltage stabilizing circuit is not afraid of load open circuit, but it is strictly prohibited to load completely short circuit.
C, drive LED with voltage stabilizing drive circuit, each string needs to add appropriate resistance to make each string of LED display brightness average;
D, brightness will be affected by voltage changes from rectification. 2, according to the circuit structure classification (1)
Resistance, capacitor step-down mode: through the capacitor step-down, in the use of flashing, due to the role of charge and discharge, the instantaneous current through the LED is very large, easy to damage the chip.
It is easily affected by grid voltage fluctuation, and the power supply has low efficiency and low reliability. (2)
Resistor step-down mode: through the resistor step-down, it is greatly disturbed by the voltage change of the power grid, and it is not easy to make a regulated power supply. The step-down resistor consumes a lot of energy, therefore, the power supply efficiency of this power supply mode is very low, and the reliability of the system is also low. (3)
Conventional transformer step-down mode: the power supply is small in size, heavy in weight and low in power efficiency, generally only 45% ~ 60%, so it is rarely used and has low reliability. (4)
Electronic transformer step-down mode: the power supply efficiency is low and the voltage range is not wide, generally 180 ~ 240 V, large ripple interference. (5)
RCC Buck mode switching power supply: the voltage stabilizing range is relatively wide and the power supply efficiency is relatively high, which can generally reach 70% ~ 80%, the application is also wide.
Since the oscillation frequency of this control mode is discontinuous, the switching frequency is not easy to control, the load voltage ripple coefficient is also relatively large, and the abnormal load adaptability is poor. (6)
PWM control mode switching power supply: it is mainly composed of four parts: Input rectifier filter part, output rectifier filter part, PWM voltage stabilizing control part and switching energy conversion part.
The basic working principle of PWM switching voltage stabilization is that under the condition of input voltage, internal parameters and external load changes, the control circuit conducts closed-loop feedback through the difference between the controlled signal and the reference signal, adjust the pulse width of the main circuit switching device to make the output voltage or current of the switching power supply stable (That is, the corresponding regulated power supply or constant current power supply).
The power supply efficiency is extremely high, generally 80% ~ 90%, stable output voltage and current.
Generally, this kind of circuit has perfect protection measures and belongs to high reliability power supply.
Application scope: it mainly provides driving capability for LED spotlights, LED light bars, LED street lamps, LED bulbs, LED underground lamps, LED ceiling lamps, LED flat panel lamps, LED wall washing lamps and other LED lamps.
Its most important feature is waterproof, can be used outdoors, and not afraid of rain, fog, direct sunlight and other harsh environment.